Ancient Monuments

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Elan Valley Pillboxes

A Scheduled Monument in Rhayader (Rhaeadr Gwy), Powys

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Latitude: 52.2645 / 52°15'52"N

Longitude: -3.5965 / 3°35'47"W

OS Eastings: 291141

OS Northings: 264127

OS Grid: SN911641

Mapcode National: GBR 9D.ZK4T

Mapcode Global: VH5CV.MB0W

Entry Name: Elan Valley Pillboxes

Scheduled Date: 16 September 2008

Source: Cadw

Source ID: 1277

Cadw Legacy ID: RD266

Schedule Class: Defence

Category: Pillbox

Period: Post Medieval/Modern

County: Powys

Community: Rhayader (Rhaeadr Gwy)

Traditional County: Radnorshire


The monument consists of three reinforced concrete pillboxes, which date to the early period of the Second World War (AD 1940-41). They were built to defend the Garreg-ddu weir and Foel valve tower in the Elan Valley Reservoirs, key structures required to maintain the public water supply to Birmingham. The pillboxes were built at regular intervals into the top of a steep W-facing slope, overlooking the NE end of the viaduct over Garreg-ddu weir and the Foel tower. The pillboxes are variants of the standard War Office FW3/22 specification and were built from reinforced concrete with inner and outer red clay brick shuttering. They are regular hexagons in shape on plan and measure 4.65m in length, 4.16m in width and 2 m in height. The walls measure 0.47m in thickness. Each pillbox possessed six embrasures and a simple N- or NW-facing entrance, protected by an external blast wall. The internal cast concrete anti-ricochet wall is of an unusual design, as it is mounted on supportive legs and resembles six stub walls radiating from a central point.

The monument is of national importance for its potential to enhance our knowledge of World War II anti-invasion practices. The monument is well preserved and is an important relic of actions taken against the perceived threat of German sabotage at vulnerable points. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. The importance of the monument is further enhanced by the group value shared by the individual items.

The areas scheduled comprise the remains described and areas around within which related evidence may be expected to survive. Area A, B and C are circular measuring 20m in diameter and centred on NGR 91171 64069, NGR SN 91128 64117 AND NGR SN 91121 64192 respectively.

Source: Cadw

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